detect when LCD is really just BW, and remark the glyph as that.
allows us to take a much faster blitter.
TODO: inform SkGlyphCache of this, so it can shrink its allocation
for the image buffer (since BW takes up 1/16 as much ram)
TODO(2): allow for A8->BW conversion my having scalercontext set a flag
if it really-wants A8 (i.e. we have a maskfilter)
git-svn-id: http://skia.googlecode.com/svn/trunk@2301 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/ports/SkFontHost_win.cpp b/src/ports/SkFontHost_win.cpp
index 8cf8535..4a2e377 100755
--- a/src/ports/SkFontHost_win.cpp
+++ b/src/ports/SkFontHost_win.cpp
@@ -600,10 +600,12 @@
// correspond to an embedded bitmap font, but not sure.
// LayoutTests/fast/text/backslash-to-yen-sign-euc.html
//
- glyph->fWidth += 4;
- glyph->fHeight += 4;
- glyph->fTop -= 2;
- glyph->fLeft -= 2;
+ if (glyph->fWidth) { // don't outset an empty glyph
+ glyph->fWidth += 4;
+ glyph->fHeight += 4;
+ glyph->fTop -= 2;
+ glyph->fLeft -= 2;
+ }
if (fHiResFont) {
SelectObject(fDDC, fHiResFont);
@@ -658,15 +660,19 @@
#include "SkColorPriv.h"
-static inline uint8_t rgb_to_a8(uint32_t rgb) {
- // can pick any component, since we're grayscale
- int r = (rgb >> 16) & 0xFF;
- // invert, since we draw black-on-white, but we want the original
- // src mask values.
- return 255 - r;
+// always packed xxRRGGBB
+typedef uint32_t SkGdiRGB;
+
+// gdi's bitmap is upside-down, so we reverse dst walking in Y
+// whenever we copy it into skia's buffer
+
+static inline uint8_t rgb_to_a8(SkGdiRGB rgb) {
+ // can pick any component (low 3 bytes), since we're grayscale
+ // but must invert since we draw black-on-white
+ return ~rgb & 0xFF;
}
-static inline uint16_t rgb_to_lcd16(uint32_t rgb) {
+static inline uint16_t rgb_to_lcd16(SkGdiRGB rgb) {
rgb = ~rgb; // 255 - each component
int r = (rgb >> 16) & 0xFF;
int g = (rgb >> 8) & 0xFF;
@@ -674,6 +680,99 @@
return SkPackRGB16(SkR32ToR16(r), SkG32ToG16(g), SkB32ToB16(b));
}
+static bool is_black_or_white(SkGdiRGB c) {
+ c &= 0x00FFFFFF;
+ bool isBW = 0 == c || 0x00FFFFFF == c;
+ bool isBW2 = 0 == ((c + (c & 1)) & 0x00FFFFFF);
+ SkASSERT(isBW == isBW2);
+ return isBW;
+}
+
+static bool is_rgb_really_bw(const SkGdiRGB* src, int width, int height, int srcRB) {
+ for (int y = 0; y < height; ++y) {
+ for (int x = 0; x < width; ++x) {
+ if (!is_black_or_white(src[x])) {
+ return false;
+ }
+ }
+ src = (const SkGdiRGB*)((const char*)src + srcRB);
+ }
+ return true;
+}
+
+static void rgb_to_bw(const SkGdiRGB* SK_RESTRICT src, size_t srcRB,
+ const SkGlyph& glyph) {
+ const int width = glyph.fWidth;
+ const size_t dstRB = (width + 7) >> 3;
+ uint8_t* SK_RESTRICT dst = (uint8_t*)((char*)glyph.fImage + (glyph.fHeight - 1) * dstRB);
+
+ int byteCount = width >> 3;
+ int bitCount = width & 7;
+
+ // adjust srcRB to skip the values in our byteCount loop,
+ // since we increment src locally there
+ srcRB -= byteCount * 8 * sizeof(SkGdiRGB);
+
+ for (int y = 0; y < glyph.fHeight; ++y) {
+ if (byteCount > 0) {
+ unsigned byte = 0;
+ for (int i = 0; i < byteCount; ++i) {
+ byte |= src[0] & (1 << 7);
+ byte |= src[1] & (1 << 6);
+ byte |= src[2] & (1 << 5);
+ byte |= src[3] & (1 << 4);
+ byte |= src[4] & (1 << 3);
+ byte |= src[5] & (1 << 2);
+ byte |= src[6] & (1 << 1);
+ byte |= src[7] & (1 << 0);
+ dst[i] = ~byte;
+ src += 8;
+ }
+ }
+ if (bitCount > 0) {
+ unsigned byte = 0;
+ unsigned mask = 0x80;
+ for (int i = 0; i < bitCount; i++) {
+ byte |= ~src[i] & mask;
+ mask >>= 1;
+ }
+ dst[byteCount] = byte;
+ }
+ src = (const SkGdiRGB*)((const char*)src + srcRB);
+ dst -= dstRB;
+ }
+}
+
+static void rgb_to_a8(const SkGdiRGB* SK_RESTRICT src, size_t srcRB,
+ const SkGlyph& glyph) {
+ const size_t dstRB = glyph.rowBytes();
+ const int width = glyph.fWidth;
+ uint8_t* SK_RESTRICT dst = (uint8_t*)((char*)glyph.fImage + (glyph.fHeight - 1) * dstRB);
+
+ for (int y = 0; y < glyph.fHeight; y++) {
+ for (int i = 0; i < width; i++) {
+ dst[i] = rgb_to_a8(src[i]);
+ }
+ src = (const SkGdiRGB*)((const char*)src + srcRB);
+ dst -= dstRB;
+ }
+}
+
+static void rgb_to_lcd16(const SkGdiRGB* SK_RESTRICT src, size_t srcRB,
+ const SkGlyph& glyph) {
+ const size_t dstRB = glyph.rowBytes();
+ const int width = glyph.fWidth;
+ uint16_t* SK_RESTRICT dst = (uint16_t*)((char*)glyph.fImage + (glyph.fHeight - 1) * dstRB);
+
+ for (int y = 0; y < glyph.fHeight; y++) {
+ for (int i = 0; i < width; i++) {
+ dst[i] = rgb_to_lcd16(src[i]);
+ }
+ src = (const SkGdiRGB*)((const char*)src + srcRB);
+ dst = (uint16_t*)((char*)dst - dstRB);
+ }
+}
+
void SkScalerContext_Windows::generateImage(const SkGlyph& glyph) {
SkAutoMutexAcquire ac(gFTMutex);
@@ -694,7 +793,6 @@
size_t dstRB = glyph.rowBytes();
if (isBW) {
const uint8_t* src = (const uint8_t*)bits;
- // gdi's bitmap is upside-down, so we reverse dst walking in Y
uint8_t* dst = (uint8_t*)((char*)glyph.fImage + (glyph.fHeight - 1) * dstRB);
for (int y = 0; y < glyph.fHeight; y++) {
memcpy(dst, src, dstRB);
@@ -702,26 +800,23 @@
dst -= dstRB;
}
} else if (isAA) {
- const uint32_t* src = (const uint32_t*)bits;
- // gdi's bitmap is upside-down, so we reverse dst walking in Y
- uint8_t* dst = (uint8_t*)((char*)glyph.fImage + (glyph.fHeight - 1) * dstRB);
- for (int y = 0; y < glyph.fHeight; y++) {
- for (int i = 0; i < width; i++) {
- dst[i] = rgb_to_a8(src[i]);
- }
- src = (const uint32_t*)((const char*)src + srcRB);
- dst -= dstRB;
+ const SkGdiRGB* src = (const SkGdiRGB*)bits;
+#if 0 // can't do this (yet) since caller may really want gray8 for maskfilters
+ if (is_rgb_really_bw(src, width, glyph.fHeight, srcRB)) {
+ rgb_to_bw(src, srcRB, glyph);
+ ((SkGlyph*)&glyph)->fMaskFormat = SkMask::kBW_Format;
+ } else
+#endif
+ {
+ rgb_to_a8(src, srcRB, glyph);
}
} else { // LCD16
- const uint32_t* src = (const uint32_t*)bits;
- // gdi's bitmap is upside-down, so we reverse dst walking in Y
- uint16_t* dst = (uint16_t*)((char*)glyph.fImage + (glyph.fHeight - 1) * dstRB);
- for (int y = 0; y < glyph.fHeight; y++) {
- for (int i = 0; i < width; i++) {
- dst[i] = rgb_to_lcd16(src[i]);
- }
- src = (const uint32_t*)((const char*)src + srcRB);
- dst = (uint16_t*)((char*)dst - dstRB);
+ const SkGdiRGB* src = (const SkGdiRGB*)bits;
+ if (is_rgb_really_bw(src, width, glyph.fHeight, srcRB)) {
+ rgb_to_bw(src, srcRB, glyph);
+ ((SkGlyph*)&glyph)->fMaskFormat = SkMask::kBW_Format;
+ } else {
+ rgb_to_lcd16(src, srcRB, glyph);
}
}
}